Cd、Pb及其复合污染对水芹生长、品质影响和富集特性研究

发布时间：2018-02-24 17:40

本文关键词： 水芹 Cd Pb 复合污染富集特性　出处：《安徽农业大学》2015年硕士论文　论文类型：学位论文

【摘要】：本试验以桐城水芹为材料,栽培在施有不同组合的Cd、Pb复合污染的土壤中,其中Cd(以纯镉计)设置4个浓度分别为0、1.0、2.0、3.0 mg·kg-1, Pb (以纯铅计)设置3个浓度分别为0、400、800 mg·kg-1。研究水芹不同器官对Cd和Pb的吸收、分配和积累,揭示水芹器官间Cd和Pb吸收、分配、积累的相互关系,并就Cd、Pb及其复合污染对水芹生长、营养品质等指标的影响进行探究。结果如下：(1)单一Cd污染条件下,水芹株高,平均根长、单株鲜重均随着Cd浓度的增加呈先增加后降低趋势,低浓度下略高于对照组,而水芹根数则呈现持续下降趋势。单一Pb污染和Cd、Pb复合污染对水芹以上各指标的影响均表现为：随着外施重金属浓度的升高均逐渐下降。(2)在单一污染条件下,水芹叶绿素a、叶绿素总量和叶绿素a/b的值变化趋势一致,即三者的值均随着外施Cd浓度的增加而降低,低浓度Pb处理时升高,而高浓度Pb抑制；对叶绿素b的影响则表现为：随着外施Cd浓度的增加,叶绿素b的含量升高,而随着外施Pb浓度的增加而降低。Cd、Pb复合污染条件下对叶绿素的影响,除对a/b值的影响无明显规律外,水芹叶绿素a、叶绿素b和叶绿素总量都随着污染浓度的增大而减小,且复合污染的影响始终强于单一污染。(3)叶柄中维生素C、可溶性蛋白及可溶性糖的含量受外施Cd含量、外施Pb含量以及Cd、Pb两元素的交互作用影响极显著,总体随着外施浓度的增加而减小。其中,维生素C和可溶性蛋白的含量受外施Pb浓度的影响较大,可溶性糖的含量主要受外施Cd浓度的影响,且维生素C含量受复合污染的影响表现的最为明显,均明显强于单一污染。(4)在Cd、Pb及其复合污染条件下,水芹各器官Cd含量高低顺序为：根部叶柄叶片；各器官Pb含量为根中最多,叶柄和叶片中的Pb含量基本相当。水芹各器官Cd、Pb中单一元素的吸收均随着该元素外施浓度的增加而呈上升趋势,Cd、Pb交互作用对吸收量的影响也达到极显著水平。Pb的加入对Cd元素吸收存在协同作用,加强了Cd对植物的毒害作用；Cd可降低水芹根部对Pb的吸收,从而减少对根的毒害,而在地上部分表现为协同作用。地下部重金属含量及富集系数均大于地上部。
[Abstract]:In this experiment, Tongcheng water celery was cultivated in the soil polluted by different combinations of cadmium and lead. The CD and Pb concentrations of CD and Pb were 0,400,800 mg 路kg-1.The absorption, distribution and accumulation of CD and Pb in different organs were studied to reveal the absorption and distribution of CD and Pb among the organs. The relationship of accumulation, and the effects of CD, Pb and its compound pollution on the growth and nutritional quality of water celery were studied. The results were as follows: 1) under the condition of single CD pollution, the plant height and average root length of water celery were obtained. The fresh weight of each plant increased first and then decreased with the increase of CD concentration, and was slightly higher than that of the control at low concentration. However, the root number of water celery decreased continuously. The effects of single Pb pollution and CD / Pb compound pollution on the above indexes were as follows: the concentration of heavy metal decreased gradually with the increase of the concentration of heavy metals applied out of the water. (2) under the condition of single pollution, the concentration of heavy metal decreased gradually with the increase of the concentration of heavy metals applied out of the water. The values of chlorophyll a, total chlorophyll and chlorophyll a / b were the same, that is, the values of chlorophyll a, chlorophyll a / b and chlorophyll a / b all decreased with the increase of CD concentration, but increased at low concentration of Pb, but inhibited by high concentration of Pb. The effect on chlorophyll b was as follows: the content of chlorophyll b increased with the increase of CD concentration, but decreased with the increase of Pb concentration. Except that there was no obvious effect on a / b value, chlorophyll a, chlorophyll b and total chlorophyll content of water celery decreased with the increase of pollution concentration. The effects of compound pollution on the contents of vitamin C, soluble protein and soluble sugar in petiole were significantly affected by CD application, Pb application and the interaction of CD and CD Pb. The contents of vitamin C and soluble protein were greatly affected by the concentration of Pb, and the content of soluble sugar was mainly affected by the concentration of CD. The effect of compound pollution on the content of vitamin C was the most obvious, which was obviously stronger than that of single pollution.) under the condition of CD / Pb and its compound pollution, the order of CD content in each organ of water celery was as follows: leaf petiole of root; The content of Pb in each organ was the highest in root. The content of Pb in petiole and leaf is basically the same. The absorption of single element in CD _ (1) Pb of water celery organs is increasing with the increase of application concentration of the element. The interaction of CD ~ (2 +) ~ (2 +) Pb also has a significant effect on the absorption of CD ~ (2 +) ~ (2 +) ~ (2 +). In addition, there is a synergistic effect on the absorption of CD, The toxic effect of CD on plants was enhanced. CD could reduce Pb absorption in the root of water celery, thus reducing the toxicity to the root, but it showed synergistic effect in the aboveground part. The heavy metal content and enrichment coefficient in the underground part were higher than those in the aboveground part.
【学位授予单位】：安徽农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X53;S645.9

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